Tubular combustion chamber for an mhd generator



31 9 -l 1 SR SEARGH KUUM F1 P 85 Q 2 GP; 3 9 4 78 236 Nov. 11, 1969 A. R. TYRRELL 3,478,

TUBULAR COMBUSTION CHAMBER FOR AN MHD GENERATOR Filed Aug. 7, 1967 5 Sheets-Sheet l m LL INVENTORZ- ALBERT RALPH TYRRELL Nov. 11, 1969 A. R. TYRRELL 3,473,236

TUBULAR COMBUSTION CHAMBER FOR AN MHD GENERATOR Filed Aug. 7, 1967 3 Sheets-Sheet 2 INVENTORZ- ALBERT RALPH TYRRELL Nov. 11, 1969 A. R. TYRRELL TUBULAR COMBUSTION CHAMBER FOR AN MHD GENERATOR Filed Aug. '7, 1967 3 Sheets-Sheet 5 FIG.4.

INVENTOR ALBERT RALPH TYRRELL United States Patent US. Cl. 310-11 3 Claims ABSTRACT OF THE DISCLOSURE Tubular combustion chamber, particularly for a magnetohydrodynamic (MHD) electrical generator, constructed from a plurality of flat-sided tubes sealingly secured together sidc-by-side throughout their lengths and through which coolant is passed. A pipe communicates with the interior of the combustion chamber through an aperture formed in at least one of the tubes defining a wall of the combustion chamber and extending transversely through said tube or tubes from the outside to the inside of said wall. The pipe may be used for introducing fluid to or extracting fluid from the combustion chamber, for permitting a probe to be inserted into the combustion chamber or to house an inspection port. The pipe is itself provided with coolant passages through which coolant is extracted from the upstream portion of the or each tube interrupted by the aperture and through which fresh coolant is introduced into the downstream portion of the or each of said interrupted tubes, thereby to provide cooling in the or each interrupted tube at substantially the same rate as in the uninterrupted tubes.

The invention relates to a tubular combustion chamber of the kind, hereinafter referred to as the kind described, constructed from a plurality of flat-sided tubes sealingly secured together side-by-side throughout their lengths and through which coolant is passed between header passages at each end of the tubes.

The invention is particularly concerned with a tubular combustion chamber of the kind described to be used to supply hot gas to a magnetohydrodynamic electrical generator (referred to hereinafter as a MHD generator). A combustion chamber for a MHD generator is described in copending application No. 658,686, filed Aug. 6, 1966 (British application No. 35,294/66). In that combustion chamber it is essential that the fluid pressure at the downstream ends of all the tubes defining the combustion chamber shall be substantially the same, thereby to ensure that the heat transfer rate from each tube shall be substantially the same.

An object of the present invention is to provide in a wall of a tubular combustion chamber of the kind described a transverse aperture through at least one of the tubes without substantially alfecting the coolant pressure at the downstream end of the tube or tubes through which it passes. The purpose of such an aperture may be for introducing or extracting fluid from the combustion chamber, for permitting a probe to be inserted therein or to house an inspection port.

According to the invention, a tubular combustion chamber of the kind described is provided with a pipe communicating with the interior of the combustion chamber through a transverse aperture formed through at least one of the tubes defining a wall of the combustion chamber from the outside to the inside of said wall, the pipe being bounded by two part-annular, noncommunicating chambers extending throughout substantially the whole length of the pipe, one of said chambers communicating with the downstream end of the upstream portion of 3,4l78,236 Patented Nov. 11, 1969 each tube interrupted by the pipe and with a coolant delivery pipe leading therefrom, and the other of said chambers communicating with the upstream end of the downstream portion of each interrupted tube and with a coolant supply pipe leading thereto, whereby coolant can be extracted through said coolant delivery pipe and further coolant can be introduced through said coolant supply pipe at such pressure that the rate of heat transfer through the upstream and downstream portions of each interrupted tube is substantially the same as through an uninterrupted tube.

Conveniently the pipe is cylindrical and is bounded by an annular coolant jacket divided by a pair of diametrically opposite walls extending through substantially the whole length of the pipe and hence defining with the inner and outer cylindrical walls of the jacket said two noncommunicating part-annular chambers, the latter each being semicyclindrical in shape. In the latter case, the coolant passing through the chambers also cools the pipe walls.

A tubular combustion chamber of the kind described for a MHD generator and including one form of pipe in accordance with the invention will now be described, by way of example, with reference to the accompanying drawings, in which:

FIGURE 1 is a diagrammatic perspective view of the combustion chamber having a wall containing said pipe;

FIGURE 2 is a plan view of the pipe shown in FIG- URE 1;

FIGURE 3 is a vertical section through the pipe on the line CC in FIGURE 2;

FIGURE 4 is a vertical section through the pipe on the line BB in FIGURE 2, and

FIGURE 5 is a transverse section through the pipe on the line DD in FIGURE 4.

The combustion chamber illustrated in FIGURE 1 is described in the aforesaid copending application and is for supplying hot gas to a MHD generator. The combustion chamber has an upstream end (at the left hand side of FIGURE 1) of square cross-section and a downstream oblique end of rectangular cross-section and is bounded by four walls formed from flat-sided tubes 1 and 2 sealingly secured together throughout their lengths. Coolant (e.g., water) is passed through all the tubes 1 and 2 from inlet header passages (not shown) at the ends of the tubes at the upstream end of the chamber to an outlet header passage (not shown) common to all the tubes 1 and 2 at the downstream end of the chamber. As explained in the copending application, the pressure of the coolant at the downstream ends of all the tubes 1 and 2 is required to be substantially the same, thereby to ensure that substantially the same rate of heat transfer occurs through all the tubes.

The pipe 5, in accordance with this invention, communicates with the interior of the combustion chamber through a transverse aperture formed in the upper wall of theachamber and interrupting several of the tubes 1. A similar pipe may communicate through another wall of the chamber. The pipe 5 is formed by a pair of cylindrical radially spaced tubes 6, 7 forming an annular jacket (see FIGURES 3 to 5). The jacket is divided into two semicylindrical, noncommunicating chambers 9, 10 by a pair of diametrically opposite partitions 8 (shown in FIG- URES 4 and 5) extending through substantially the whole length of the pipe and by an appropriately shaped plate 8a welded to the lower end of each partition 8 and to the adjacent tube 1. The chamber 9 communicates at the inner end of the pipe 5 with the downstream ends of the upstream portions, indicated at 1a in FIGURES 3 and 4, of all the tubes 1 which have been interrupted by the hole formed in the upper wall of the chamber. The chamber 10 communicates at the inner end of the pipe with the upstream ends of the downstream portions, indicated at 1b in FIGURES 3 and 4, of all the tubes 1 which have been interrupted by the hole formed in the upper wall of the chamber. The outer end of the pipe 5 is provided with a flange 11 containing a pair of part-annular galleries 12, 13 communicating with the chambers 9 and 10 respectively. The gallery 12 communicates with a coolant outlet connection 14 and the gallery 13 communicates with a coolant inlet connection 15, both being formed in the flange 11. Coolant flowing through the upstream portions 1a of the interrupted tubes 1 is passed through the chamber 9 and the outlet connection 14 in the direction of arrows 16, shown in FIGURE 3, such that the rate of heat transfer through each of the upstream portions 1a of the interrupted tubes 1 is substantially the same as through the corresponding portion of each of the uninterrupted tubes 1. Also, fresh coolant is introduced through the connection 15 and flows through the chamber 10 to the downstream portions 1b of the interrupted tubes 1 in the direction of arrows 17, shown in FIGURE 3. The rate of flow and the pressure of the said fresh coolant are such that the coolant pressure at the downstream end of each of the downstream portions 1b of the interrupted tubes 1, the pressure drop and the rate of heat transfer therethrough are substantially the same as for the corresponding portion of each of the uninterrupted tubes 1. The passing of coolant through the chambers 9 and 10 also cools the pipe 5.

In FIGURES 3 and 4, the pipe 5 is shown as being open at each end thereof. It can therefore be used to introduce a fluid into the combustion chamber or to extract a fluid therefrom. The pipe 5 may be closed by a transverse window of quartz or similar material at any convenient position in its length and hence may form an inspection port. Alternatively or additionally, the pipe may be closed by a removable closure means, such as a cap or bung, or contain a transverse wall having an aperture therein for receiving a probe.

In FIGURES 1 and 3, the downstream ends of the tubes 1 are shown to be outwardly curved and positioned adjacent a U-shaped tube 3, through which coolant is passed. This tube is described in the aforesaid copending application.

What I claim as my invention and desire to secure by Letters Patent of the United States is:

1. A tubular combustion chamber of the kind constructed from a plurality of flat-sided tubes sealingly secured together side-by-side throughout their lengths and through which coolant is passed, wherein the improvement comprises a pipe communicating with the interior of the combustion chamber through an aperture formed in at least one of the tubes defining a wall of the combustion chamber and extending transversely through said tube from the outside to the inside of said wall, the pipe being bounded by two part-annular, noncommunicating chambers extending throughout substantially the whole length of the pipe, one of said chambers communicating with the downstream end of the upstream portion of each tube interrupted by the pipe and the other of said chambers communicating with the upstream end of the downstream portions of each interrupted tube, a coolant delivery pipe leading from said one chamber and a coolant supply pipe leading to said other chamber, whereby coolant can be extracted through said coolant delivery pipe and further coolant can be introduced through said coolant supply pipe at such pressure that the rate of heat transfer through the upstream and downstream portions of each interrupted tube is substantially the same as through an uninterrupted tube.

2. A tubular combustion chamber as claimed in claim 1 including means defining an annular cooling jacket defining said pipe and a pair of diametrically opposite walls extending longitudinally through substantially the whole length of the jacket and defining with inner and outer cylindrical walls thereof said two noncommunicating, part-annular chambers, the latter each being semicylindrical in shape.

3. A tubular combustion chamber as claimed in claim 1 for supplying hot gas to a magnetohydrodynamic electrical generator.

References Cited UNITED STATES PATENTS 2,126,524 8/1938 Wood l22-23S 3,309,546 3/1967 Boll 3l011 DAVID X. SLINEY, Primary Examiner US. Cl. X.R. 

